(1) Field of the Invention
The present invention relates to a separator for deflection yoke, and particularly to a deflection yoke separator which not only exactly adjusts the convergence of electron beams, but also reinforces the strength of the neck portion of the deflection yoke.
(2) Description of the Prior Art
In a shadow mask type color television, R, G, B electron beams projected from an electron gun pass through a hole formed in the shadow mask simultaneously, and land on the relevant phosphorescent dots, thereby producing the intended colors. Under this condition, if the three colors are not correctly combined, the color is deviated, or other problems are produced.
The above mentioned problematic phenomenon can occur over the whole picture, or it is confined to the peripheral portions of the picture. In the former case, the deviation of the convergence of the R, G, B beams is the cause, while, in the latter case, the faulty phenomenon is attributed to the difference between the curvature of the phosphor face and the curvature of the beam receiving face.
Meanwhile, the distance between the deflecting centre of the deflection coil and the face of the shadow mask are varied at each moment by the momentary deflecting position, and therefore, it is known to be a difficult task to correct the misconvergence.
Such correction of the convergence is classified into a dynamic correction and a static correction, the dynamic correction being carried out by manipulating the electron gun and the deflection yoke, and the static correction being carried out by varying the magnetic fields of the deflection yoke through attachment of a steel piece or a magnet on the proper position.
Meanwhile, the deflection yoke is formed through a medium of a separator taking a separated symmetrical form, and, in carrying out the static correction, an object is attached on the separator.
FIG. 3 is an exploded perspective view of the conventional separator employing the above described method, and as shown in this drawing, the separator takes a trumpet shaped body A consisting of a combination of two symmetrical pieces. The trumpet shaped body A comprises: a neck holder H surrounding the neck of the cathode ray tube, and a flange F extended in a direction perpendicular to the axis of the holder H. In carrying out the static correction according to the conventional method, correcting means M such as steel pieces or magnets are attached at the proper places on both the neck holder H and the flange F.
However, in carrying out the correcting by using the objects, the worker has to watch the picture state and at the same time has to adjust the position of the magnet to decide the proper position. Then, the steel pieces or the magnets are attached by means of an adhesive. However, the exploring and deciding of the proper positions are not easy for the neck holder H, although it may by easy for the flange F.
That is, the correcting means M such as steel pieces and magnets take an arcuate shape so as for them to be attachable on the outer surface of the neck holder H. In deciding the positions of the correcting means, the worker has to turn the pieces around the neck holder H, but there is no means temporarily fixing the pieces. Therefore it is difficult to decide the exact position, and further, when attaching the pieces by means of an adhesive after the deciding of the positions, it is no less difficult to find out the predetermined positions.
Such difficulties act as an impediment not only for the productivity but also for the product quality.